Radiographic testing uses x-rays or gamma rays to detect internal flaws in materials. It works on the principle that denser materials absorb more radiation, causing variations in radiation transmission that can be recorded on film. The key steps are positioning the radiation source and film, exposing the material to radiation, developing the film, and evaluating it to locate flaws appearing as darker or lighter zones. Proper film density between 2-4 is important for clearly distinguishing flaws. Factors like radiation source, material thickness and density determine radiation penetration and absorption levels.

1. RADIOGRAPHIC
TESTING

2. Radiographic Testing
•“Based on the principle of preferential radiation
Transmission and Absorption.”

3. X-Ray Machine (aimed down)

4. Radiation Absorption
•“Thicker, or higher density materials
absorb more radiation, resulting in less
transmission to the film.”

5. Absorption vs Thickness

6. Aluminum 2.70
Steel 7.87
Copper 8.96
Lead 11.34
Tungsten 19.30
Metal Densities
Grams/cubic centimeter

7. Absorption vs Density

8. Radiation Types
• Gamma radiation sources
– Iridium 192
– Cobalt 60
– Cesium 137
• X-Ray
– Machine

9. RT Steps
• Position radiation source
• Position film behind object
• Expose radiation
• Develop film
• Evaluate

10. Film Density Vs Flaws
• Darker film zones:
• Cracks, slag, porosity
• Incomplete joint penetration
• Lighter film zones:
• Tungsten inclusions
• Melt through, reinforcement

11. 2 T hole
1 T hole
4 T hole
Hole Type Image Quality
Indicators

12. Wire Type Image Quality Indicators

13. RT Equipment
• Radiation source
– X-ray machine
– Gamma radiation source
• Radiation monitor
• Film holders
• IQI’ s
• Densitometer / film
density strips
• Film processor
• Film viewers

14. Orientation of Source, Plate, & Film

15. RT Advantages
• Detects subsurface flaws
• Used for all materials
• Film is permanent record
– If stored properly

16. RT Limitations
• Radiation hazard
• Requires access to both sides
• Flaw orientation
• Flaw types
• Film interpretation

17. RT Results
• Film
• Video tape
• Sketches

18. RADIOGRAPHIC
TEST
• SCOPE:
• Radiographic testing is one of
the volumetric NDT method to detect internal
defects of any material
PRINCIPLE :
Differential absorption of energy in a medium
making use of high frequency of electro
magnetic waves (X-and Gamma rays)

19. R.T REQUIREMENTS
For Radiography the main requirements are
1) Source of Energy (X- Ray & Gamma Rays)
2) Object to be Radiograph (welds, castings,
forging)
3) Recording medium (Film)
X-rays & gamma rays are having the lowest
wave lengths(10 -8to 10-11)m or 1 to 100 Aº

20. 1) Travel in straight lines with the speed of light.
2) Exposes the film.
3) Reveal internal discontinuities.
4) Not affected by magnetic field.
5) Cannot be detected by five sense.
6) Penetrate through all the materials and all the
mediums.
R T CONT……

21. GENERATION OF X-RAYS
Radiation
Penetrate
the Sample
X-rays are generated from
Electrical equipment
Consisting of a vacuum tube
With two electrons inside.
(Anode, Cathode)

22. Filament heated with a low current (5ma to
10ma).
Anode maintained with very high voltage (DC
potential) (kilo voltage 200kv to 450kv).
The electron strikes to the target material
(Tungsten).
GENERATION OF X-RAYS
CONT…..

23. X-rays are produced and
sent through the window.
The output of X-ray is a
combination of
characteristic X-ray and
continuous X-ray.
Electrons passes through
continuous.
GENERATION OF X-RAYS
CONT…..

24. X-RAY UNIT CONTROLS
Kilo voltage for anode
Millie amperage for filament
Timer for exposure (in minutes).
Portable units (up to 200kv)
Mobile units ( above 200kv to 450kv)
All portable units are Uni-polar type .(H
W D C)
All mobile units are Bipolar type. (F W D C)

25. Step up transformers are used to step up
kilo voltage from primary to secondary coils.
For bipolar type double diode used
for voltage rectification.
X-RAY UNIT CONTROLS
CONT……...

26. GAMMA RAYS
CHARGE MASS
ELECTRONS ―VE CHARGE 1/1840 UNIT
PROTONS +VE CHARGE 1 UNIT
NEUTRONS NIL ≈ 1 UNIT
ELEMENT MOLECULE ATOM

27. Electrons and protons are equal in number.
Neutrons vary according to chemical valency.
Atomic number ―› no of protons
Mass number ―› no of protons
+ no. of neutrons.
GAMMA RAYS
CONT……

28. ISOTOPES
77 Ir191 +n I r192 (ISOTOPE)
(IRIDIUM)
27 Co 59 +n Co 60(ISOTOPE)
(COBALT)
Elements having same atomic number, but different
mass number are called Isotopes.
GAMMA RAYS
CONT……

29. Properties of Isotopes
1) UNSTABLE.
2) DECAY.
3) IONISATION.
4) EMIT GAMMA RAYS.

30. Activity of Isotope (conversion)
1 Curie (Ci)=3.7x10 10 d. p. s
d. p. s= disintegration per second
S.I Unit of Activity
Becquerel Bq
1Bq=1 d. p. s
1Ci=3.7x10 10 d. p. s
1Ci=3.7x10 10 Bq
1Ci=37x10 9 Bq
1Ci=37GBq
GBq Giga Becquerel

31. ROENTGEN
• The amount of X-rays or Gamma rays
Required to produce one electrostatic unit.
Of charge (+ve or –ve) in one C.C of air at
N.T.P (normal temperature pressure)
Then the input of X-ray or Gamma rays is called
one Roentgen.

32. 1 Roentgen=84Ergs
Specific Activity : No . of curies Per Gram
After The Physical Size Greater The
Specific Activity.
ROENTGEN CONT…..

33. ISOTOPES
Natural : Uranium, Radium, Radon
Artificial : Iridium, Cobalt, Thulium, Caesium
All Isotopes are decaying exponentially
due to decay, activities are reduced
DECAY OF ISOTOPES
At = A 0 .e -λt
A 0  Initial activity
A t  Final activity
λ  Decay constant
T  Period

34. S.NO ISOTOPES HALF LIFE
PERIOD
OUTPUT IN
ROENTGEN
/
HOUR/1
METER
1)
2)
3)
4)
Ir192
Co60
Cs137
Tm170
75 DAYS
5.3 YEARS
30 YEARS
130 DAYS
0.5
1.35
0.37
0.0025
ISOTOPES CONT….

35. Exposure = Intensity x Time
E = I x t
I ∞ I / D²
Where
I  Intensity for X-Rays & Gamma Rays
D Distance
ISOTOPES
CONT….

36. Relationship Between Intensity & Distance
(Inverse square law)
E = I x t ; E1 = I1 t1 ; E2 = I2 t2
I ∞ I / D² ; I1 ∞ I / D1² ; I2 ∞ I / D2²
I1 / I2 = I / D1² / I / D2²
I1 / I2 = D2² / D1²
ISOTOPES CONT….

37. RELATIONSHIP BETWEEN
TIME AND DISTANCE
• E1 = I1 t1 ; E2 =I2 t2 ;
• Now E1 = E2;
• I1 t1 = I2 t2. I1 ∞ I / D1²
I2 ∞ I / D2²
• I / D1² x t1 = I / D2² x t2
• t1 / D1² =t2 / D2²
• t1 / t2= D1² / D2²

38. ENCAPSULATION OF
ISOTOPES
• All The Activated Small Pellets of Ir192 (or)
Co60 are Enclosed in a Stainless Steel Capsule
and Seal Welded in a hot cell at the Isotope
division.
• S.S Capsule
Activated Pellets of Ir192
(OR) Co6O

39. OUTPUT OF ISOTOPES
RHM / Ci
Roentgen per hour per curie
at 1 meter distance.

40. PROPERTIES OF ISOTOPES
ISOTOPES ENERGY
LEVEL
IN “MEV”
R.H.M
PER
CURIE
PENETRATION LEVEL IN
STEEL
MILLIMETERS INCH
IrI92
RAYS
1
0.31 MEV
TO 0.60
MEV.
.5R/Hr
AT 1
MTR
D.P.S
MIN MAX
6 75
MIN MAX
¼ “ 3”
Co60
1 RAYS
1.17 MEV
1.33 MEV
1.33R/Hr
AT 1MTR
D.PS
18 200 3/4” 8’’

41. PROPERTIES CONT………..
ISOTOPES
ENERGY
LEVEL
IN MEV
R.H.M
PER
CURIE
PENETRATION LEVEL IN
STELL
MILLIMETERS INCH
Cs137 1 r-RAYS
0.66 MEV
0.4 R/ HR
AT 1MTR
D.P.S
MIN MAX MIN MAX
25 100 1” 4”

42. PENETRATION AND
ABSORPTION
• X-Rays and Gamma-Rays Penetrate
through all dense and opaque Materials.
• In Turn, the Material absorb the Radiation.
• The amount of Absorption depends upon
the Density and Thickness of Materials.
• The Absorption otherwise depends upon
the Linear Absorption Coefficient (µ )
and Thickness (x).

43. • this factor is given by the relation:
• Ix=Io .e -µx =Io/e µx.
LINEAR ABSORPTION COEFFICIENT
THICKNESS (x)
Io
Ix (FINAL INTENSITY)
(INITIAL
INTENSITY)
PENETRATION AND
ABSORPTION CONT…

44. A. Half value thickness: the thickness at
which the original intensity reduced
to Half .
x=0.693/ µ ; µ =0.693/H.V.T
B. Tenth value thickness: the thickness
at which the original intensity
reduced ten times.
x=2.303/ µ; µ =2.303/T.V.T
1T.V.T=3.323 H.V.T
1 T.V.T ≈ 3.3 H.V.T
PENETRATION AND ABSORPTION
CONT…

45. RECORDING MEDIUM (FILM)
• Recording medium in
radiography is
radiographic Film.
Source
X-Ray
Ƴ-Ray
Recording medium
(film)
Object

46. RECORDING MEDIUM (FILM)
CONT……..
• X-Ray film is made of transparent polyester base.
• On both sides of the base ,sensitive Silver Bromide
Emulsion is coated.
• This Silver Bromide Emulsion is sensitive to light,
heat, chemical fumes , ultraviolet rays, x-rays and
Gamma -rays.
• This Emulsion is Prepared coated converted and
preserved in a dark room with a safelight, temperature
and relative humidity control.

47. 1. Safe light control : Red, height is 1.25 m
2. Temperature: 20º C
3. Relative humidity: 50 to 60%
X-Ray film is double side
emulsion coated.
RECORDING MEDIUM (FILM)
CONT……..

48. CROSS SECTIONAL VIEW OF X-RAY
FILM.
SILVER
BROMIDE
COATING
10 TO 15 µ
EMULSION
COATED(1 To 2µ)
SUPER COATING (1 To 2µ)
BASE :175 µ

49. X-RAY FILM GRADES
SL.No: Grain Size Interaction Grain
Size by Radiation
Speed
1. Coarse (Large) D8 High
2. Medium Size D7 Medium
3. Fine Grain D5 Slow
4. Very Fine Grain D4 Very Slow

50. FILM PROCESSING
• After exposure in a film. the film gets darkened.
• During exposure, a latent image of the Radiographic
film.
• To enhance the Latent image as a
Real image some chemical treatment shall be given for
the exposed film in a dark room with a controlled
safelight, temperature and relative humidity.
* This chemical treatment is called film processing.

51. ORDER OF SEQUENCE IN FILM
PROCESSING
I. Developing Done in developer with
agitation(20˚C/ 5 mins)
II. Rinsing Done in stop bath (20˚/1
min)
III. Fixing Done in fixer (20˚/15 mins)
IV. Washing Done in running
water(20˚/15 mins)
V. Drying Done in drying cabinet
(40˚C/ R.H:50-60%/15
mins)

52. • After comes exposure and processing the film
becomes a radiograph with permanent
negative image.
• The two important requirements in a radiograph
are:
• (A). Density (B). Sensitivity
• (A). Density OPTICAL DENSITY DEGREE OF
DARKNESS
Density=Log10 Ii/It
Incident Intensity , It Transmitted
Intensity
Ii
ORDER OF SEQUENCE IN FILM
PROCESSING CONT….

53. SENSITIVITY
(B). Sensitivity:
Ability to see the smallest defect in Radiograph.
The Radiographic images shall have proper
contrast and definition:
Contrast by Density.
Definition by Sensitivity.

54. DENSITY RANGES
I. IF D=0 Transmission=100%
II. IF D=1 Transmission=10%
III. IF D=2 Transmission=1.0%
IV. IF D=3 Transmission=0.1%
V. IF D=4 Transmission=0.01%

55. • The Density Recommended by all Standards and Codes is:
• Minimum:2.0 Maximum :4.0
• In the above Density Range only (2.0 TO 4.0).all Defects
in the Material can be Clearly Distinguished with the use
of High Intensity illuminator Lamp Transmission Light.
• As per the ASME Sec V, Density Ranges are:
• (A). For X- Ray Min: 1.8 Max:4.0
• (B). For Gamma- Ray Min: 2.0 Max:4.0
DENSITY RANGES CONT….

56. • For Double Film Radiography, Density for A
Single Film min:1.3.
• In a Single Radiograph Density Variation Shall
be Within -15% TO +30% from the Density.
• Achieved at the area of Interest Density at the
body of (IQI).
DENSITY RANGES CONT….

57. DEFINITION
• Contrast: Difference in density between adjacent
area in a Radiograph.
• Definition: Sharpness of the out Line of the
image in Radiograph.
(A) (B)
-- - - - - - - - -
-- - - - - - - -
-- - - - - - - - -
GOOD POOR
©
GOOD
SHARP
EDGE
(D)
FUZZY
EDGE

58. CHARACTERESTIC CURVE
• Relationship Between Log Relative:
0.5
1.0
1.5
2.0
2.5
3.0
3.5
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
Density
AB Under exposure
BC Correct exposure
CD Over exposure
DE Over exposure +
Over development
AB – TOE
BC – ST.LINE
CD - SHOULDER
DE - SOLRAISATION
A B
C
D
E

59. H & D CURVE
• The characteristic curve is modified by two
scientist.
• Hurter & Driffield named as H&D Curve
O.5 1.0 1.5 2.0 2.5 3.0 3.5
3.5
3.0
2.5
2.0
1.5
1.0
0.5

60. H&D CONT……
• I. For a change in exposure from 1.0 to 1.5 Density
change is 0.5 to 0.8.
• II. For a change in exposure from 2.0 to 2.5 Density
change is 1.2 to 2.0.
• Film contrast in ii is greater than film Contrast I.
From this H&D Curve, It is established Film Contrast,
Depend upon Slope Gradient & Straight LINE Portion
of H&D Curve.
• Higher the Slope, Higher the Contrast.
• Lower the Slope, Lower the Contrast.

61. COMPARITIVE STUDY FOR
DIFFERENT GRADES OF FILM
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0
B C A

62. COMPARITIVE STUDY FOR DIFFERENT
GRADES OF FILM CONT…
• To achieve minimum Density 2.0 any Radiography Series:
FILM Exposure
time
Film A 2.3(High)
Film B 3.0
(Medium)
Film C 3.7 (Slow)

63. COMPARITIVE STUDY FOR DIFFERENT
GRADES OF FILM CONT…
• Slope C >Slope B > Slope A.
Film
“C”
High Contrast
Film
“B”
Medium Contrast
Film
“A”
Low Contrast

64. RADIOGRAPHIC QUALITY
• Radiographic quality is Affected by
SCATTERING and UNSHARPNESS.
• SCATTERING:
• 1. Internal scattering (Forward scattering)
• 2. Side Scattering.
• 3. Back Scattering.

65. INTERNAL SCATTERING
• This scattering occurs due to secondary
radiation when the primary radiation from the
radiographic source strikes the inner wall of
hollow objects, Internal Scattering occurs.
SIDE SCATTERING
• When the primary radiation from the source
strikes the side wall (or) nearby the object, side
scattering occurs.

66. Side SCATTERING
High Electrical Potential
Electrons
-
+
X-ray Generator or Radioactive Source Creates
Radiation
Exposure Recording Device
Radiation
Penetrate
the Sample
DIAPHRAM
FILM
OBJECT
LEAD MASK
LEAD SCREEN

67. BACK SCATTERING
• When the primary radiation from the source passes
through the object and film, they penetrate through the
floor in which the object is kept and returns
• As a longer wave and strikes the backside of film.
• As a result ,back scattering occurs in the Radiograph.
• Scattering shall be minimized by Using:
• FILTERS.
• DIAPHRAMS.
• MASKS.
• SCREENS.

68. UNSHARPNESS IN
RADIOGRAPHY
• (A). GEOMETRIC UNSHARPNESS.
• (B). MOVEMENT UNSHARPNESS.
• (C). INHERENT UNSHARPNESS.

69. GEOMETRIC UNSHARPNESS
• This occurs due to improper position of X-ray /
Gamma-ray, source, object & Film
OBJECT
SOURCE
FILM

70. GEOMETRIC UNSHARPNESS
CONT……..
The source (x ray / Gamma ray) shall be kept far
away from the object at the central axis of the
object.
Object and film shall be kept very close.
For Gamma - ray source:
SOD source to object distance.
OFD object to film distance.
SFD source to film distance.

71. • FOR X-RAY SOURCE:
• FOD Focal spot to object distance.
• OFD Object to film distance.
• FFD Focal spot to film distance.
• SOD (OR) FOD D
• D / t Ratio Shall Be Minimum 8 (OR)
• D / t ≥ 8
GEOMETRIC UNSHARPNESS
CONT……..

72. SOURCE
FILM
UMBRA
OBJECT
OFD
“ t “
S SMALL SOURCE
SOD
“D”
big SOURCE
PEN UMBRA
S1
S2
UMBRA
FILM
GEOMETRIC UNSHARPNESS
CONT……..
FIG:1 FIG:2
S1,S2 LARGE SOURCE
f1 f2

73. FIGURE:2 CONT…….
IN FIG2: TWO TRIANGLES ARE SIMILAR.
SOD = D ; OFD = t
S1,S2 / F1,F2 = s / µg = SOD / OFD ; s / µg=D / t
µg . D = S . t ; µg =s . t / D
THIS APPLICABLE FOR gamma- RAYS.
FOR X – RAYS, FOCALSPOT – SIZE is “ F ”
S1,S2 and F1 , F2 ARE SIMILAR
S1,S2 = SOURCE = S ; F1,F2 =µg

74. • FOR X-RAY,FOCAL SPOT SIZE IS “F”.
F / µg = FOD / OFD ; F / µg = D / t ;
µg x D = F x t ; µg = F t / D
GEOMETRIC UNSHARPNESS
CONT……..

75. GEOMETRICAL UNSHARPNESS
SHALL BE AS MINIMUM AS
POSSIBLE.
(A). For X-ray Radiography:
µg = F x t / D
1. Select smaller focal spot.
2. Keep OFD as small as possible.
3. Keep large FFD. (D)
(B). For Gamma Ray Radiography:
µg = s x t / D
1. Select smaller size source (s)
2. Keep OFD as small as possible.
3. Keep large SFD. (D)

76. AS PER ASME SEC V MAX “µg” VALUE
PERMITTED FOR DIFFERENT THICKNESS
OF MATERIAL GIVEN.
SLNO JOB THICKNESS IN
INCHES
MAX. µg VALUE
IN “mm”
1. UPTO 1” 0.25
2. 1” TO 2” 0.50
3. 2” TO 3” 0.75
4. 3” TO 4” 1.00
5. ABOVE 4” 1.25

77. All unsharpness in radiography shall be minimized
to the smallest extent.
This will enable the radiography to maintain
good quality.
GEOMETRIC UNSHARPNESS
CONT……..

78. GEOMETRICAL UNSHARPNESS.
While setting up a job for radiography proper
geometrical consideration shall be taken care of
during exposure set up for source, object& film.
This will control the Geometrical
unsharpness.

79. MOVEMENT UNSHARPNESS.
• While taking radiography with the source, object
and film, there are frequent changes for
vibration of source object & film.
• Which results in “Movement unsharpness”.

80. INHERENT UNSHARPNESS.
• Inherent unsharpness occurs due to film
graininess.
• This will be very high in coarse grain size films.
• Always select medium size grain films to
minimize this inherent unsharpness.

81. RADIOGRAPHIC SCREENS.
Radiographic screens are used in the film
cassette along with the radiographic film, while
taking Radiographs.
The Main Purpose Of The Screens Are:
(1). To reduce scattering.
(2). To improve photographic
action.

82. CLASSIFICATION OF
RADIOGRAPHIC SCREENS.
• Radiographic screens are classified into three
categories:
• (A). Metallic screens.
• (B). Fluoro metallic screens.
• (C). Fluorescent screens.
• For industrial radiography mostly metallic screens are
used.
• Occasionally fluorometallic screens are used.
• For medical radiography fluorescent screens used.

83. R.T.SCREEN CONT….
• Metallic screens are made of a thick cardboard
over which a thin layer of high dense material
such as copper or lead is coated .
• The thickness of metal layer over coating on the
cardboard varies .
• According to the energy level of X-ray or -
Gamma rays used for radiography.

84. SELECTION OF METALLIC
SCREENS
S.NO PROPERTIES OF
MATERIAL
LEAD COPPER
1 DENSITY 11-
6gm/c.c
8.8gm/C.C
2. GRAINSIZE FINE
GRAIN
COARSE
GRAIN
3. COST LOW HIGH
4. FLEXIBILITY GOOD POOR

85. SELECTION CONT…..
• In all properties, lead is better than copper.
LEAD OXIDE
COATING
CARD
BOARD

86. FILM CASSETTE
• Film cassette is loaded with X-ray film and one
pair of lead screens.
• While loading the film in a dark room.
• The X-ray film shall be sand witched by two lead
screens .
• 1. Front screen.
• 2. Back screen.

87. ENERGY LEVEL
SLNO
:
ENERGY LEVEL THICKNESS
OF LEAD
OXIDE
COATING
1. IRIDIUM 192 0.10 TO
0.15MM
2. XRAY TUBE (UPTO
450 KV)
0.10 TO
0.15MM
3. COBALT 60. 0.25MM TO
0.40MM
4. 1 MEV TO 4MEV 0.25MM TO
0.40MM

88. SENSITIVITY
• Ability to detect smallest defect in
radiography is called Radiographic
sensitivity.
• Sensitivity in radiography is achieved
using image quality indicators (IQI) placed
on the job while taking radiography.
• Image quality indicators (IQI) or
penetrametres used in radiography shall
be able to define radiographic quality.

89. I.Q.I SETS
I. DIN WIRE TYPE DIN 54109
II. ASTM STRIP HOLE
TYPE
ASTM.E.1025
III. BSS/AFNOR STEP HOLE
TYPE
BS3971
IV. ASTM WIRE TYPE ASTM.E.747

90. DIN IQI TYPES CONT……..
DIN 62 FE
1 ISO 7
DIN 62 FE
10 ISO 16

91. ASTM I.Q.I TYPES.

92. I.Q.I CONT……..
• IQI Shall be available in all series in all materials.
LOW
DENSE
MATERIALS
MEDIUM
DENSE
MATERIALS
HIGH
DENSE
MATERIALS
ALUMINIU
M
(AL)
IRON
(Fe)
COPPER
(CU)

93. I.DIN-54109-WIRE TYPE IQI
• Din-54109-wire type IQI:
• 16 wires are arranged in 3 sets.
• Each set consists of 7 wires.
• The wire diameters are in ”mm” only.
• They are in G.P series in descending order.

94. DIN -TYPE CONT………
WIR
E
NO
DIA
IN
MM
WIR
E
NO
DIA IN
MM
WIRE
NO
DIA IN
MM
WIRE
NO
DIA
IN
MM
WIRE
NO
DIA
IN MM
WIRE
NO
DIA
IN
MM
1 3.2 4 1.6 7 .8 10 .4 13 .20 16 .1
2 2.5 5 1.25 8 .63 11 .32 14 .16
3 2.0 6 1.0 9 .5 12 .25 15 .125

95. DIN -TYPE CONT………
• Every successive wire diameter reduces to 4/5
times of preceding wire diameter .
every 4th wire diameter reduced to half.
• After every tenth wire the diameter reduced by
10 times.

96. SELECTION OF DIN-IQI
S.NO: JOB THICKNESS IQI
1. UPTO 20 MM 10 ISO16
2. 20 TO 40 MM 6 ISO 12
3. ABOVE 40 MM 1 ISO 7

97. DIN-TYPE IQI CONT….
DIN 62 FE
1 ISO 7

98. SENSITIVIT
Y
THICKNESS OF LEAST
VISIBLE WIRE
x100
% SENSITIVITY=
JOB THICKNESS IN MM

99. ASTM-STRIP HOLE TYPE.IQI
• ASTM:e:1025
• ASTM IQI is a
rectangular piece with
uniform thickness.
• There are three holes in
strip hole type IQI.
• They are 4t,1t,2t.
FE25
4T 1T 2T

100. ASTM IQI CONT….
4T 1T 2T
T THICKNESS OF IQI
Fe STANDARDS FOR MATERIAL

101. ASTM IQI HOLE TYPE
• ASTM IQI Hole type
selection:
2-4T 2.8%
2-2T 2.0 %
2-1T 1.4 %
1-4T 1.4 %
1-2T 1 %
1-1T 0.7 %
%Equivalent
Sensitivity =100/ x TH/2
X JOB THICKNESS.
T THICKNESS OF IQI.
H LEAST VISIBLE HOLE.

102. STEP HOLE TYPE I.Q.I
B.S.S/ AFNOR:B.S.S:3971.
• These IQI are used in U.K and France in industrial
radiography.
• In this group there are two types :
• I. Rectangular type.
• Hexagonal type.
I. Rectangular step hole type.
SIDE VIEW
TOP VIEW
IN EACH STEP, THERE IS A HOLE. THE DIA OF HOLE EQUAL TO
CORRESPONDING STEP THICKNESS.

103. HEXAGONAL STEP HOLE TYPE
There are six steps in this I.Q.I. In each step there is a hole.
The hole Dia is equal to the corresponding step thickness.

104. ASTM WIRE TYPE IQI.E.747
ASTM-wire type penetrameter consists of 21
wires. The wire diameter are in inches. They
are grouped in four sets .
each set consists of six wires. They are in G.P
series in ascending order.

105. ASTM WIRE TYPE IQI.E.747 CONT....
WIRE
NO
DIA IN
INCHES
WI
RE
NO
DIA IN
INCHES
WI
R
E
N
O
DIA IN
INCHE
S
WIR
E
NO
DIA IN
INCHE
S
WI
RE
NO
DIA
IN
INCH
ES
WIR
E
NO
DIA IN
INCHE
S
WIR
E
NO
DIA IN
INCHE
S
1. 0.0032” 4. 0.0064” 7. 0.0128” 10. 0.0256” 13. 0.05” 16. 0.10” 19. 0.20”
2. 0.004” 5. 0.008” 8. 0.016” 11. 0.032” 14. 0.064
”
17. 0.128” 20. 0.256”
3. 0.005” 6. 0.01” 9. 0.02” 12. 0.04” 15. 0.08” 18. 0.160. 21. 0.32”

106. Each successive wire diameter is 5/4 th of the
preceding wire.(Example):1st wire 0.0032”, 2nd wire
:0.004”.
After three successive wires the fourth wire
diameter is double that of first wire . (example):1st
wire 0.0032”,fourth wire 0.0064”.
After ten successive wires, the eleventh wire
diameter is increased to ten times of the
corresponding first wire.(Example):1st wire
0.0032”,11th wire 0.032”.
ASTM WIRE TYPE IQI E.747
CONT….

107. A.S.T.M E.747
In each set six successive wires are arranged in a
group with a plastic pouch.
Set no:, material standards wires nos are
designated by lead letters and lead numbers.

108. A.S.T.M E.747

109. A.S.T.M E.747 CONT..
The quality of the radiographs are well defined
by IQI or penetrameter.
In general the IQI shall always be placed only on
the source side in the unfavorable are as while
taking radiography.

110. IMPORTANT REQUIREMENTS
FOR IQI SELECTION:
Small in size.
Shall be available in all sizes in all
materials.
Easy for interpretation.
Sensitivity data shall be
satisfactory for all techniques in
radiography.

111. IMPORATANT REQUREMENTS
ARE IQI SELECTION:
(A). Smaller size.
(B). Shall be available in all series
in materials.
Easy for interpretation.
Sensitivity data shall be
satisfactory for all
technique in radiography.

112. R.T.TECHNIQUES
There are four types of
techniques in radiography:
1. Single wall single image- SWSI
2. Double wall single image- DWSI
3. Double wall double image- DWDI
4. Panoramic

113. SWSI-TECHNIQUE.
Among all the four techniques SWSI
technique is the best technique.
In this single wall single image
technique, radiography quality is
very well controlled.
by keeping d/ t ratio as high as
possible.

114. Geometrical unsharpness (µ)can be reduced very
well. This will improve the definition of
radiographic image.
SWSI-TECHNIQUE.

115. FILM
C
A B
RADIATION SOURCE
x
1.1x
t=25mm
SOURCE
WELD PLATE
IQI
S.W.S.I TECHNIQUE
FRONT VIEW OF RADIOGRAPHY SET UP.

116. SWSI-TECHNIQUE.CONT…..
• SOURCE:IR.192.
• SIZE: 2X2.5.
• OC=40cms.
• AC=18cms.
• AB=36cms.
• D/T=400mm/25mm=16mm.
• µg=st/D=2 x 25/400=1/8
• µg=0.125mm.

117. DOUBLE WALL SINGLE IMAGE
TECHNIQUE.DWSI
• DWSI technique shall be used for
taking radiographs of pipe weld .
• Any hollow cylindrical part with
uniform wall thickness having
o.D≥4’’ pipe.

118. DWSI TECHNIQUE CONT……………
)
(
SOURCE
(Ø2X2.5MM)
FILM
PIPE WELD
Ø400X25MM
IQI

119. DWSI TECHNIQUE CONT….
• For this pipe weld ø400x25 segments (ab,
bc, cd, da) are taken for radiography.
• IQI wire type:6 ISO 12.
• IQI ASTM strip hole type. Astm:17
• Both IQI’ s are placed on film side with a
lead letter “F” for identification of DWSI
technique.
SOURCE
A
B
C
FILM

120. DWSI TECHNIQUE CONT….
• For better sensitivity:
• In din62fe 6iso12,5 wires are seen.(6,7,8,9,10).
• In ASTM 17,two holes shall be seen.(4t & 2t).

121. DOUBLE WALL DOUBLE IMAGE (DWDI)
• Any hollow cylindrical part with uniform
wall thickness having O.D 3½ and less.
• O.D≤3½” or 88mm, is taken with DWDI
technique.
• There are two types in DWDI:
• 1.Dwdi super imposed image technique.
• 2.Dwdi elliptical image technique.

122. D.W.D.I. CONT………..
• SUPER IMPOSED IMAGE TECHNIQUE:
FILM
SOURCE

123. D.W.D.I. CONT………..
ELLIPTICAL IMAGE TECHNIQUE
SOURCE.
FILM

124. D.W.D.I. CONT………..
In the above technique, IQI shall be
placed on source side.
For µg calculations, O.D of the tube
is taken as thickness, for d/ t ratio and
µg studies fig:1, source is placed
exactly above the weld.
In fig:2, source is shifted by 10˚
angle from the centre, so that top weld and
bottom weld are formed in film.

125. PANAROMIC TECHNIQUE
• This technique is used to take radiography of
circumferential seam welds of large O.D pipes, shells,
drums.
• This techniques shall be used for radiography of similar
type of castings.
• This also be used for taking radiography of sphere
welds.

126. PANORAMIC TECHNIQUE
CRANK
DEVICE
RADIATION
SOURCE
GUIDE
TUBE
TECH /OPS
IRIDIUM CAMERA
DEVICE CABLE

127. CROSS SECTIONAL VIEW OF
CIRCUMFERENTIAL WELD.
In this technique, films are placed on the outside
covering each segment with one inch overlap on
either side of each segment.
Minimum number of IQI’ s shall be placed
inside the shell are three numbers at each 120˚
location.

128. CROSS SECTIONAL VIEW OF
CIRCUMFERENTIAL WELD.CONT….
120°
120°
120°
IQI
IQI
IQI
SOURCE AT
CENTRE

129. CROSS SECTIONAL VIEW OF
CIRCUMFERENTIAL WELD.CONT….
This condition holds good only for panoramic exposure
of circumferential weld radiography.
Before taking radiography, two extra films shall be
placed on any two segments.
After radiography without disturbing the radiography
set up.
One of the extra films shall be carefully removed and
sent for processing to check the density level.

130. CROSS SECTIONAL VIEW OF
CIRCUMFERENTIAL WELD.CONT….
If the density is less than 2.0,continue the
exposure for some more time to meet the
required density 2.0.
If the first film shows higher density.

131. PANORAMIC TECHNIQUE ……..
Panoramic technique can very well be arranged
for taking radiography of similar type of
castings arranged in a circle with films placed on
the back side of all casting.
The radiation source can be centered and
radiography taken covering all castings in a
single exposure.

132. PANORAMIC TECHNIQUE ……..
RADIATION
SOURCE
CASTING
FILM
A
B
C
D
NO. 0F FILM
AB
BC
CD
DA

133. PANORAMIC TECHNIQUE FOR SPHERE
WELDS ….
The Source Shall Be Centered Inside For Each
Stage And Radiography Shall Be Taken By
Placing The Films Outside At Each Side.

134. PANORAMIC TECHNIQUE FOR
SPHERE WELDS CONT……
L4 L5
L1 L2 L3
C.S2
C.S3
SOURCE
INSIDE

135. RADIOGRAPHIC
INTERPRETATION

136. Art of extracting maximum information
from radiography image.
This requires subjective judgment of the
interpreter.

137. STEPS IN THE R.T TEST.
STEP 1: Produce the radiograph.
STEP 2: Determine The Quality Of The
Radiographic image.
STEP 3: Interpret All Indications.
STEP 4: Evaluate the test and test
results.
STEP 5: Record and communicate test
results.

138. STEPS IN THE R.T
TEST.CONT….
Interpret: to give the meaning
of to explain.
Evaluate : to determine the
worth of something.

139. STEPS IN THE R.T
TEST.CONT….
• Indication: a density change appearing on a
radiograph.
• False indications: film artifacts, screen Problems,
fog, scatter x-ray diffraction.
• Discontinuity: a break in the test specimen’s
structural continuity.
• Defect: a condition that renders the specimen
unsuitable for intended service.

140. FACTORS AFFECTING THE
INTERPRETATION OF TEST
RESULTS:
• Type of materials being welded.
• Type of weld and joint preparation.
• Welding processes.
• Radiographic process.
• Radiographic technique.
• The applicable code or standard.

141. FUNCTION OF A QUALIFIED
INTERPRETER.
1.Define radiographic quality.
Analysis of R.T technique and development
regarding procedures.
2: analysis the radiographic image to determination
of the nature and extent of any abnormal
deviation.

142. FUNCTION OF A QUALIFIED
INTERPRETER CONT…
3. Evaluate by comparing the
interpreted.
Information with standard / specification.
4. Report results: accurately and
clearly.

143. QUALITIES DESIRED FOR A
GOOD INTERPRETER.
1. KNOWLEDGE.
2. EXPERIENCE.
3. VISION ACUITY.
(A). EYE VISION FREE FROM COLOUR
BLINDNESS.
(B). NEAR VISION ---J2.

144. TOOLS REQUIRED FOR
PROPER INTERPRETATION.
(A). Working environment to produce maximum
comfort and minimum fatigue for
interpreter.
(B). Room with sub due lightening. The back
ground lightening shall be equal to the
transmitted light through the radiograph.
No glare or reflected light.
(C). Good illuminator with light intensity
suitable for the of density. Uniform
distribution of light.
300 – 100 candles / square meter.

145. TOOLS REQUIRED FOR
PROPER INTERPRETATION.
CONT…
(D). Densitometer and density
comparison strips.
(E). Reference radiographs.
(F). Magnifying glass and glass
marking pencil.

146. VIEWING OF RADIOGRAPHS.
SLNO: OBJECTIVE SUB.OBJECTIVE
(INDIVIDUALS)
1. ILLUMINATOR VISUAL ACUITY
2. BACKGROUND
LIGHTINING
TRAINING
3. FILM TYPE KNOWLEDGE
4. CONTRAST EXPERIENCE
5. IMAGE
MAGNIFICATION
AGE
6. DISTANCE OF VIEWING DARK
ADAPTATION

147. RADIOGRAPHIC
INTERPRETATION
Get all facts and give a balanced judgment.
Reporting:
1. Unambiguous and concise.
2. Phrases like “no significant defects”
should be avoided.
3. Report should locate the
defect, name, size, and possible depth.
4. Sketches can accompany report indicating
location and nature of defect.

148. HANDILING THE
RADIOGRAPH
1. Hold the radiograph with the
fingers across the edges.
2. The film has to be clipped to
the illuminator, use corners.
3. Never touch the surface.

149. HANDILING THE RADIOGRAPH
CONT..
4. Examine the film with reflected light for
processing quality, drying marks, stains etc.
5. Check for the graininess over
development and too high temperature causes
excessive graininess.

150. EXPOSURE
CALCULATIONS,VARIABLES.
1. GEOMETERY.
2. SOURCE TYPE AND STRENGTH.
3. FILMS-----TYPE.
4. SCREENS.
5. DENSITY.
6. STEEL EQUIPMENT.
7. MATERIAL THICKNESS.
8. CONTROL OF SCATTER.

151. INTERPRETER SHOULD HAVE
KNOWLEDGE OF THE
FOLLOWING:
The characteristics of radiation source and
energy level with respect to material being
tested.
The characteristics of recording media (film) in
response to selected source and energy level.
The processing of recording media with
respect to image quality.
The product form being radiographed.

152. INTERPRETER SHOULD HAVE
KNOWLEDGE OF THE
FOLLOWING:
The possible and most probable types of
discontinuities that can occur .
The possible variation of discontinuity images as
a function of radiographic geometry and other
factors.

153. R.T STANDARDS,CODES
&.SPECIFICATIONS
Standards.
Specifications.
Codes.
Recommended standards.
Procedures.
These are documents which indicate the buyer
the quality and other requirements of a
component/system services.

154. STANDARDS ARE PREPARED BY
THE FOLLOWING:
I. A company BHEL
II. A group of organization with like
interest.
III. NATIONAL BUREAU OF
STANDARDS.(EX): BIS, DIN, ANSI.
IV. INTERNATIONAL STANDARDS.
(EX): ASME, API, AWS, TEMA.

155. CLASSIFICATION OF
STANDARDS PRETAINING TO
RADIOGRAPHY:
STANDARDS PRETAINING TO IMAGE
QUALITY.
EXAMPLE : E747,E.1025.
DIN 54109
AFNOR NF.A04-304
ISS 3657
BSS 3971.

156. STANDARDS ARE PREPARED BY
THE FOLLOWING. CONT…
Standards pertaining to method of test.
Radiographic arrangement criteria for film selection,
selection of radiation energy etc….
example:
ASTM-E94.
BSS-2600,2910.
DIN-54112.
ASME-SEC V ARTICLE:2.
JIS-23104,23105.
ISS-2595.

157. STANDARDS ARE PREPARED BY
THE FOLLOWING. CONT…
Standards pertaining to specific structures and products:
Specify testing methods and specific component such as
Boilers, Pressure Vessels, Pipe Lines etc.
ASME SEC I,III,VIII
B.S.S 5500.
API 6A,1104

158. STANDARDS ARE PREPARED BY
THE FOLLOWING. CONT…
Collection of reference Radiographs.
Classifying defects by their shape, size, and
distribution etc…
example: E.446,E.186,E.280,E.390.
IIW collection of reference radiographs of
welds.
Standards pertaining to RADIATION SAFETY.

159. A document in corporating details to be carried out for
meeting the code/ standard/ specification &
requirements.
A STEP
PROCEDURE